One of the joys of Rio’s southern districts—this in a city of mountains and hills—is their flat topography and network of bike paths, plus shared bicycles at stations all over the map. It’s as easy as downloading the Bike Rio app, grabbing one of the two-wheelers they call laranjinhas, and heading out to Lagoa Rodrigo de Freitas. Less than a half-mile from Ipanema beach, the lagoon is an idyllic postcard featuring the Tijuca jungles plus Corcovado in the background. All told, it’s five miles around, with views that change at every curve—and don’t forget the city’s spectacular sunsets.